Detachable Coil Incorporating Stretch Resistance

• US 20160206322A1
• Filed: 03/25/2016
• Published: 07/21/2016
• Est. Priority Date: 07/27/2007
• Status: Active Grant

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Fitz, Matthew J., Lei, Cathy, Gulachenski, Joseph, Castaneda, Maricruz, Currie, Gary
• Granted Patent: US 10,076,338 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61B 17/12145 having a pre-set deployed three-dimensional shape methods of manufacturing A61B2017/00526
• CPC Class Codes: A61B 17/12154 having stretch limiting means
• CPC Class Codes: A61B 2017/12068 detachable by heat
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/9505 having retaining means other than an outer sleeve, e.g. male-female connector between stent and instrument

Abstract

An implantable embolic device having a stretch-resistant member passing therethrough that also serves as a tether for connecting the device to a delivery system. The stretch-resistant member is attached at a proximal and distal end of the device and extends proximally to the delivery device. The proximal attachment point serves to isolate a distal, stretch resisting segment of the member from axial tension placed on a proximal, connecting section of the member. Thus, the portion of the stretch-resistant member being used to connect the embolic device to a delivery device may be placed under tension without placing tension or distorting the implant.

Claims

1. A detachable implant delivery system, comprising:

a delivery device having a distal end and a heater proximate said distal end;

a microcoil;

a tether connected to said microcoil and to said delivery device, said tether including;

a first section extending through said microil and fixed at a distal location of said microcoil; and

,

a second section extending proximally from said first section;

said second section being attached to a proximal location on said microcoil and to a location on said delivery device proximal of said heater;

wherein said second section of said tether has a higher tension than said first section of said tether, such that said second section enhances breakage of said tether during activation of said heater and said first section resists stretching to retain an original configuration of said microcoil.

2. The detachable implant delivery system of claim 1, wherein said first section is attached to said microcoil with a knot.

3. The detachable implant delivery system of claim 1, wherein said first section is attached to said microcoil with adhesive bonding.

4. The detachable implant delivery system of claim 1, wherein said tether comprises a material selected from the group consisting of polyolefin, polyethylene, polyolefin elastomers, ethylene-octene copolymer, biodegradable materials, PGLA, hydrogel, acrylamide, PEG, PET, nylon, amide-based polymers, block copolymers, PEBAX, polypropylene.

5. The detachable implant delivery system of claim 1, wherein said microcoil further comprises a hydrogel material.

6. The detachable implant delivery system of claim 1, wherein said first section of said tether is connected at said distal location of said microcoil by melting said tether to form a ball.

7. The detachable implant delivery system of claim 1, wherein first section is attached to said microcoil via an overhand knot, a half stitch, or a surgeon'"'"'s knot.

8. A detachable implant delivery system, comprising:

a delivery device having a heater coil proximate a distal end of said delivery device;

a microcoil comprising a helical wire; and

,

a stretch-resistant member characterized by a single monofilament and connecting said delivery device and said microcoil;

said stretch-resistant member passing through a lumen of said microcoil and being attached at a first location near a distal end of said microcoil, at a second location near a proximal end of said microcoil, and at a third location near a distal end of said delivery device, such that said stretch-resistant member is located within said heater coil;

wherein a first portion of said stretch-resistant member is between said second location and said third location is tensioned so as to enhance breakage upon application of heat by said heater coil, and wherein a second portion of said stretch-resistant member is isolated from the tension of said first portion so as to resist stretching and thereby retain an original configuration of said microcoil.

9. The detachable implant delivery system of claim 8, wherein said stretch-resistant member is attached to said microcoil at said first location with a knot.

10. The detachable implant delivery system of claim 8, wherein said stretch-resistant member is attached to said microcoil at said first location with adhesive bonding.

11. The detachable implant delivery system of claim 8, wherein said stretch-resistant member comprises a material selected from the group consisting of polyolefin, polyethylene, polyolefin elastomers, ethylene-octene copolymer, biodegradable materials, PGLA, hydrogel, acrylamide, PEG, PET, nylon, amide-based polymers, block copolymers, PEBAX, polypropylene.

12. The detachable implant delivery system of claim 8, wherein said microcoil further comprises a hydrogel material.

13. The detachable implant delivery system of claim 8, wherein said second section of said stretch-resistant member is connected at said distal location of said microcoil by melting said tether to form a ball.

14. A method of detaching a microcoil from an implant delivery system, comprising:

advancing a delivery system within a patient;

activating a heater located at a distal end of said implant delivery system;

heating a first section of a tether that is pre-tensioned between a first location on said implant delivery device so as to enhance breakage along said first section of said tether;

said tether further connecting to a second location at a proximal end of said microcoil so as form a second section;

breaking said tether along said first section so as to release tension between said first location and said second location;

maintaining connection of said second section of said tether at said second location and at a third location at a distal end of said microcoil;

said second section being isolated from changes in tension between said first location and said second location so as to resist stretching to retain an original configuration of said microcoil.

15. The method of claim 14, wherein said tether comprises a material selected from the group consisting of polyolefin, polyethylene, polyolefin elastomers, ethylene-octene copolymer, biodegradable materials, PGLA, hydrogel, acrylamide, PEG, PET, nylon, amide-based polymers, block copolymers, PEBAX, polypropylene.

16. The method of claim 14, wherein said tether is tied with a knot at said third location.

17. The method of claim 14, wherein said tether is connected at said distal end of said microcoil by melting said tether to form a ball.